Abstract: A disk device has a housing structure capable of reducing unnecessary vibrations of the base of the disk device by improving the rigidity thereof. A bath-tub type base of the disk device includes a damping structure on the bottom or on the sides adjacent to the bottom for attenuating the vibrations of the base. Apparatus for writing a reference signal into the disk of the device using a reference head with a head insertion hole formed in the base is also provided.

Abstract: A memory storage disk module comprising a memory storage disk unit including at least one memory storage disk, and at least one head able to access the disk for writing and reading data to and from the disk, and a control circuit board. A cover is provided to cover the memory storage disk unit and the control circuit board, and the cover constitutes a shield against an emission of electromagnetic waves, as well as a duct for a flow of cooling air. The cover is composed of a substantially solid main panel portion and front and rear panel portions having small apertures, respectively, allowing air to flow therethrough. A memory storage disk system comprises a plurality of memory storage disk modules, and a rack having the memory storage disk modules therein releasably mounted and being substantially unaffected by electromagnetic waves.

Abstract: A memory storage disk module comprising a memory storage disk unit including at least one memory storage disk, and at least one head able to access the disk for writing and reading data to and from the disk, and a control circuit board. A cover is provided to cover the memory storage disk unit and the control circuit board, and the cover constitutes a shield against an emission of electromagnetic waves, as well as a duct for a flow of cooling air. The cover is composed of a substantially solid main panel portion and front and rear panel portions having small apertures, respectively, allowing air to flow therethrough. A memory storage disk system comprises a plurality of memory storage disk modules, and a rack having the memory storage disk modules therein releasably mounted and being substantially unaffected by electromagnetic waves.

Abstract: Disclosed is a method of manufacturing a spindle motor using a fluid bearing. The spindle motor includes a hub having a support member for supporting a disk storage medium and a magnet, a fixed member having a coil, for holding the hub rotatably, and a fluid bearing provided between the hub and the fixed member. In this method, the hub is secured to the fixed member through the fluid bearing. This method includes a step of grinding a support surface of the support member. In this grinding step, a grinding member is applied to a part of the support member, and other part of the support member is pressurized by a pressurizing member to prevent the hub from falling down due to the pressurization by the grinding member.

Abstract: Three kinds of stop patterns are recorded at the same cylinder position of at least three recording surfaces of disk media. Each pattern is a division pattern in which one circumference is divided into two portions and which are recorded therein. Phases of the division patterns are sequentially deviated in the circumferential direction every 120.degree.. When a motor is activated, the motor stop position is detected on the basis of the stop patterns of the disk media and activating conditions to rotate the motor in a predetermined direction, thereby activating the brushless DC motor having no Hall sensor.

Abstract: A method of fixing a suspension to an actuator arm having a mounting portion. The mounting portion has a first hole and a second hole formed in proximity to the first hole. The suspension has a cylindrical projection having an outer diameter slightly smaller than the diameter of the first hole. The cylindrical projection is first inserted into the first hole of the mounting portion of the actuator arm, and a ball having a diameter slightly larger than the diameter of the second hole of the mounting portion of the actuator arm is next forcibly passed through the second hole. Accordingly, the second hole is radially expanded to deform a wall portion defining the first hole, thereby forcibly pressing the cylindrical projection on the mounting portion of the actuator arm to fix the suspension to the actuator arm.

Abstract: A magnetic circuit structure in a disk unit which can be manufactured at low costs. The magnetic circuit includes a main yoke manufactured by stacking a plurality of rolled steel plates and connecting them together by caulking. The magnetic circuit further includes an inner magnet, an outer magnet, and a side yoke all of which are mounted on the main yoke. Both ends of the inner magnet abut against a pair of shoulders formed on the main yoke, and both ends of the outer magnet abut against a pair of shoulders formed on the main yoke. Vertical movement of the inner magnet is prevented by a pair of presser plates and fixed to the main yoke, and vertical movement of the outer magnet is also prevented by a pair of presser plates and fixed to the main yoke.

Abstract: An apparatus for fixing a suspension to an actuator arm has a mounting portion. The mounting portion has a first hole for fixing the suspension and a second hole for injecting an adhesive. The second hole is substantially perpendicular to the first hole and communicates with the first hole. A spacer having a cylindrical projection having an outer diameter slightly smaller than the diameter of the first hole is spot-welded to a base end portion of the suspension. The cylindrical projection of the spacer fixed to the suspension is inserted into the first hole of the mounting portion of the actuator arm, and the adhesive is next injected through the second hole into the first hole, thereby fixing the suspension to the mounting portion of the actuator arm by means of the adhesive injected.

Abstract: In a disk unit containing in a predesignated size, an arm, read/write heads secured to an end of arm, a printed circuit board, and leads connecting read/write heads to the printed circuit board, the disk unit of the present invention is realized by:employing a straight-type arm in place of a conventional dog-leg shaped arm; providing a structure for mounting a printed circuit board on a side of the disk unit where a space is made by employing the straight-type arm; moving a printed circuit board conventionally mounted above the disks to the above-mentioned space, thus evacuating the upper part of the disks; and providing additional disks in the above-mentioned evacuated upper part of the disks to increase storage capacity of a disk unit.

Abstract: In a disk unit containing in a predesignated size, an arm, read/write heads secured to an end of arm, a printed circuit board, and leads connecting read/write heads to the printed circuit board, the disk unit of the present invention is realized by:employing a straight-type arm in place of a conventional dog-leg shaped arm;providing a structure for mounting a printed circuit board on a side of the disk unit where a space is made by employing the straight-type arm;moving a printed circuit board conventionally mounted above the disks to the above-mentioned space, thus evacuating the upper part of the disks; andproviding additional disks in the above-mentioned evacuated upper part of the disks to increase storage capacity of a disk unit.

Abstract: A divided housing for supporting magnetic disk devices therein is described. The housing is separated into a shell which supports a magnetic disk pack and a magnetic head positioner, and a cover to close the opening of the shell. Spindles of the disk pack and the head positioner are respectively held at opposite ends by ball bearings. Supporting holes for supporting the bearings are formed in side walls of the shell facing each other with one boring process. The centers of the bearings are aligned precisely coaxial to each other. The plane which separates the housing into the shell and the cover intersects the side walls almost parallel to the line connecting the center of both spindles, but away from those supporting bearings. The supporting holes are perface circles, and the open edge of the shell has no cut-in portion or grooves. This increases mechanical stength of the shell, and assures a stable holding of the spindles. Therefore, the reliability of the magnetic disk device is improved.

Abstract: A divided housing for supporting magnetic disk devices therein is described. The housing is separated into a shell which supports a magnetic disk pack and a magnetic head positioner, and a cover to close the opening of the shell. Spindles of the disk pack and the head positioner are respectively held at opposite ends by ball bearings. Supporting holes for supporting the bearings are formed in side walls of the shell facing each other with one boring process. The centers of the bearings are aligned precisely coaxial to each other. The place which separates the housing into the shell and the cover intersects the side walls almost parallel to the line connecting the center of both spindles, but away from those supporting bearings. The supporting holes are perfect circles, and the open edge of the shell has no cut-in portion or grooves. This increases mechanical stength of the shell, and assures a stable bolding of the spindles. Therefore, the reliability of the magnetic disk device is improved.